Ice-maker treatment system

ABSTRACT

A system for disinfecting water in an ice-making machine having a water inlet for receiving an incoming stream of water, a supply of recirculating water, a reservoir for containing the supply of recirculating water, a transport conduit for transporting water from the reservoir, and an evaporator plate which receives water from the transport conduit and over which at least one of the incoming stream and the recirculating supply can flow to form ice. The system comprises a device for treating at least one of the incoming stream and the recirculating supply in the transport conduit before the water from either flows over the evaporator plate.

BACKGROUND OF THE INVENTION

The present invention relates to the treatment of drinking waterdesigned for use in commercial ice-making machines, and morespecifically to an apparatus, system, and method for ensuring that icemade in an ice-making machine is made with treated water.

Conventional commercial ice-making machines are susceptible tomicroorganism growth and contamination, and to scale build-up. For thesake of efficiency, in most such machines a volume of water isintroduced into the machine and recirculated over a cold surface until aproper volume of ice has formed. As water begins to form ice, and theamount of water available for recirculation lessens, the amount of waterbeing circulated through the machine can be replenished from an outsidesource. If there are microorganisms in the incoming water, in therecirculating water, in the air, or on surfaces inside the machine, theice which is formed by the machine may become contaminated. In addition,dirt particles in the incoming water, in the recirculating water, in theair, or on surfaces inside the machine, can act as nuclei for scalebuild-up, which can cause clogging in the machine.

Conventional ice-making machines address the problems of microbialcontamination and scale formation by treating the water before it entersthe ice-making machine. Such treatment can involve disinfection and/orfiltration techniques. Disinfection can reduce the microbial content ofthe incoming water, while filtration can remove certain microbes, aswell as dirt particles, from the water.

Certainly, treatment of the incoming water in the above-described mannercan reduce the number of microorganisms and/or dirt particles in thewater entering the icemaking machine. However, any microorganisms thatsurvive the initial disinfection of the water may still have theopportunity to flourish, as the water is repeatedly recirculated throughthe machine. In addition, any contaminants on interior surfaces of themachine, and any airborne contaminants within the machine, will haveample opportunity to contaminate the recirculating water prior to thewater being transformed to ice, and to act as nuclei for scale build-upThus, when equipped with treatment systems which treat only the incomingwater, conventional ice-making machines fail to solve the problems ofcontaminated water being used to form ice, and of dirt particles actingas nuclei for scale build-up.

Accordingly, it is an object of the present invention to provide animproved system for treating the water used to make ice in an ice-makingmachine.

It is another object of the present invention to provide a retrofit unitfor converting conventional ice-making machines to ice-making machinesutilizing the present treatment system.

SUMMARY OF THE INVENTION

The above-listed objects are met or exceeded by the present system fortreating water in an ice-making machine, wherein either or both theincoming flow of water and the flow of recirculating water is/aretreated prior to flowing over the cooling surface of the ice-makingmachine.

More specifically, the present invention provides a system for treatingwater in an ice-making machine having a water inlet for receiving anincoming stream of water, a supply of recirculating water, a reservoirfor containing the supply, a transport conduit for transporting waterfrom the reservoir, and an evaporator plate, which receives water fromthe transport conduit and over which at least one of the incoming streamand the recirculating supply of water can flow to form ice. Theice-making machine includes a device for treating at least one of theincoming stream and the recirculating supply in the transport conduitbefore the water flows over the evaporator plate.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic view of a conventional ice-making machine of thetype well-known in the prior art;

FIG. 2 is a schematic view of an ice-making machine equipped with thetreatment device of the present invention;

FIG. 3 is a schematic view of the preferred embodiment of the treatmentsystem of the present invention;

FIG. 4 is a schematic view of an alternate embodiment of the treatmentdevice of the present invention;

FIG. 5 is a schematic view of a second alternate embodiment of thetreatment device of the present invention;

FIG. 6 is a schematic view of a third alternate embodiment of thetreatment device of the present invention;

FIG. 6A is an enlarged fragmentary portion of FIG. 6;

FIG. 7 is a schematic view of a fourth alternate embodiment of thetreatment device of the present invention; and

FIG. 8 is an alternate embodiment of the ice-making machine of thepresent invention.

DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring to FIG. 1, a conventional commercial ice-making machine isshown and generally designated 10. Such machines 10 are well known inthe art, and are designed, constructed, and operate for the most partlike the machine described in detail in U.S. Pat. No. 5,527,470 to Suda,which is hereby incorporated by reference.

Machines 10 of this type are often used in restaurants, hotels, fastfood outlets, and similar establishments, and basically operate to turnwater into ice cubes or crushed ice. The machine 10 includes anevaporator plate 12, a reservoir 14, a recirculating pump 16, a feedconduit 18, and a water distributor 20, all of which are in fluidcommunication with each other. The water distributor 20 has a pluralityof openings 22 for distributing water in a cascading fashion down theface of the evaporator plate 12.

The evaporator plate 12 is covered with a number of preferablyspheroidal or polygonal-shaped pockets 13 (only a few of which areshown), and is chilled by means well known in the art. As a result, acertain amount of the water passing over the evaporator plate 12collects in the pockets 13 and freezes to the plate, thus forming ice.That water which does not freeze on the evaporator plate 12 returns tothe reservoir 14, where it is pumped in a stream 15 back up the feedconduit 18 by the recirculating pump 16.

An incoming stream of water 24 to be used in ice-making is introduced tothe machine 10 via a water inlet 25. The entry of the incoming water 24is controlled by a water control valve 27, such as a float valve or asolenoid valve, in a manner well known in the art. The valve 27 keepstrack of the level of water in the reservoir 14, and when the level ofwater gets too low, the valve opens to allow more water to enter themachine 10 through the water inlet 25.

Conventionally, the incoming water 24 is treated before it enters themachine 10, through exposure to a treatment device 26. The treatmentdevice 26 operates by exposing the water 24 to any of a number ofwell-known treatment technologies, including disinfection and filtrationtechnologies. Examples of such treatment technologies are described morefully below, and include exposure to ultraviolet light,micro-filtration, chemical or other known disinfection technologies, andmechanical filtration.

As pointed out previously, one of the major disadvantages of thisconventional arrangement is that any microorganisms which survive theone-time disinfection, along with any airborne contaminants within themachine 10, and contaminants on the interior surfaces of the machine,will still have ample opportunity to flourish and/or act as nuclei forscale build-up in the water as it recirculates through the machine.Contaminated water may, of course, lead to contaminated ice, while scalebuild-up can interfere with the efficient operation of the machine.Reduction or elimination of these problems are objects of the presentinvention.

Referring now to FIG. 2, an ice-making machine incorporating thetreatment system of the present invention is shown and generallydesignated 28. Those features shared with the ice-making machinedepicted in FIG. 1 are identically numbered and named. Depending uponthe position of the valve 27, the incoming stream of water 24periodically enters the ice-making machine 28 via the inlet 25. Theincoming water 24 enters the reservoir 14 and mixes with any wateralready present in the reservoir. Next, the water in the reservoir 14 ispumped by the recirculation pump 16 up and through a transport conduitor tube 30 in the stream 15 toward the water distributor 20.

On its way to the water distributor 20, the transport conduit 30operationally encounters a treatment device 32, which treats the stream15 being carried in the transport conduit. The treated stream 15 thencontinues along the transport conduit 30 until it reaches the waterdistributor 20, at which point the stream flows through a plurality ofholes 22 in the distributor and passes over the surface of theevaporator plate 12. As described previously, the evaporator plate 12 iscooled, and some of the water flowing over it will freeze to the pockets13 in its surface, eventually forming ice cubes.

Placement of the treatment device 32 in this manner, so that all waterin the stream 15 flowing through the transport conduit 30 toward theevaporator plate 12 must first be treated, is one of the major featuresof the present invention, in that it greatly reduces the chance of icebeing made from contaminated water, and greatly reduces the opportunityfor scale build-up. Where treatment of the water involves filtration, inaddition to removal of certain microbes, removal of dirt capable offorming a nucleus for scale build-up is also achieved.

According to the preferred system of the present invention, all water inthe stream 15 traveling through the transport conduit 30 toward theevaporator plate 12, whether fresh water from the inlet stream 24 orrecirculated water from the recirculating supply which collects in thereservoir 14 after passing over the evaporator plate, must firstencounter the treatment device 32. Thus, the stream 15 is treated justprior to passing over the evaporator plate 12, which reduces thepossibility of the ice being formed from contaminated water.

It is contemplated that the treatment device 32 may incorporate a widevariety of treatment technologies. Examples are shown in FIGS. 3-7, anddescribed below.

Referring now to FIG. 3, the treatment device 32 is shown incorporatingan ultraviolet lamp 34. The use of ultraviolet light in waterdisinfection is well known in the art. The lamp 34 should be of themercury-vapor type, and should produce the majority of its energy at awavelength around 254 nanometers, a wavelength known to be effective inkilling microorganisms in water. An ultraviolet ballast 35 is preferablyconnected to the lamp 34 to stabilize the current flowing to the lamp.

When the treatment device 32 is an ultraviolet lamp 34, in the preferredembodiment the transport conduit 30 is a tube made of a material that istransparent to ultraviolet radiation, such as TEFLON® brandperfluoro(ethylene-propylene) copolymer ("FEP") or quartz. TEFLON® brandFEP tubes 30 provide a non-stick surface, which reduces the likelihoodof contaminants in the stream 15 adhering to an inner surface of thetube and blocking the path of the ultraviolet light. In addition, a tube30 made of TEFLON® brand FEP will not be brittle, and thus will be lesssusceptible to breakage than glass tubing would be. Furthermore, in theunlikely event that breakage occurs, by using TEFLON® brand FEP tubes 30instead of glass, one avoids the possibility of pieces of broken glassbecoming mixed with the ice being formed by the ice-making machine 28.

Still referring to FIG. 3, in the preferred embodiment the tube 30 iswound into an approximately helical or spiral shape, and is positionedso that the ultraviolet lamp 34 is located in the approximate center oraxis of the spiral formed by the tube. Shaping the tube 30 andpositioning the ultraviolet lamp 34 in this manner increases thelikelihood, in at least two ways, that any contaminants in the stream 15being transported through the tube will be exposed to ultravioletradiation emitted from the lamp.

First, water turbulence is increased by forcing the stream 15 tonegotiate bends in the tube 30. Greater turbulence in the stream 15 willshake up, dislodge and/or suspend contaminants in the water, increasingthe chance that such contaminants will be exposed to, and destroyed by,the ultraviolet radiation being emitted from the lamp 34. Second, inline with the principle that the shortest distance between two points isa straight line, having the stream 15 flow through a spiral path meansthat the length of the journey of the stream past the ultraviolet lamp34 is longer. This increases the amount of time that the stream 15, andany contaminants in that stream, will be exposed to the ultravioletradiation emitted from the lamp 34. Also, to increase the total exposureof the stream 15 passing through the spiral wound tube 30, it iscontemplated that the tube may be placed in a housing 36 made ofpolished aluminum or any other reflective material, which will act as areflector for the ultraviolet radiation being emitted by the lamp 34.

Although a spiral or helical configuration of the tube 30 is preferred,with the ultraviolet lamp 34 positioned in the approximate center oraxis of the spiral or helix, other shapes and configurations arecontemplated, which operate to increase the exposure time of the stream15 to the lamp.

Referring now to FIG. 4, an alternate embodiment of the treatment deviceof FIG. 3 is shown and generally designated 32a, in which the tube 30asimply passes alongside the ultraviolet lamp 34. It is also contemplatedthat the treatment device 32a may utilize a radiation source other thanan ultraviolet lamp 34. It is further contemplated that the treatmentdevice 32a and the transport tube 30 may be provided as a retrofit unitwith necessary couplings and fittings (not shown) to permit adaptationof conventional ice machines 10 to utilize the system of the presentinvention.

Referring now to FIG. 5, another embodiment of the present invention isdepicted and generally designated 32b. In this embodiment, the treatmentdevice comprises an ozone generator 37 in combination with a venturieductor 38. Ozone is a very powerful water disinfectant, as is wellknown in the art. As the stream 15 of water flows through the transportconduit 30b, it encounters the venturi eductor 38 and a vacuum iscreated, sucking ozone out of the ozone generator 37 and into the water.Introducing ozone into the water disinfects the water It is alsocontemplated that a chlorine gas generator could be substituted for theozone generator 37. Chlorine is another well known and effective waterdisinfectant.

Referring now to FIGS. 6 and 6A, another embodiment of the presentinvention is designated generally 32c, in which the treatment device 32cincludes a hollow fiber filter 40. The stream of water 15 flows throughthe tube 30 and into the treatment device 32cthrough an inlet 42, whereit encounters the hollow fiber filter 40. The hollow fiber filter 40 ismade up of a large number of hollow fibers 44, each having an outersurface 46 and an inner surface 48. The outer surfaces 46 are providedwith pores 50 (FIG. 6A). The incoming stream of water 15 is forcedthrough the pores 50, into a hollow space 51 between the outer 46 andinner 48 surfaces of the fibers 44, and out through an outlet 52 of thetreatment device 32c. Pores 50 having a diameter of approximately 0.02microns are known to be small enough to filter out any bacteria in thestream of water 15 being forced through the filter 40. It is alsocontemplated that the hollow fibers 44 could be replaced by a membranehaving similarly sized pores.

Referring now to FIG. 7, yet another embodiment of the present inventionis generally designated 32d. Here, the treatment device 32d includes afilter 54 containing a resin 56 halogenated with bromine or iodine,which are known to be effective disinfectants. The incoming stream 15enters the filter 54 through the tube 30d and passes through thehalogenated resin 56, where it comes into contact with the bromine oriodine and is accordingly disinfected. In order to get to the outlet 58the water must pass through a screen 60, where contaminants can befurther removed. It is also contemplated that the filter 54 alternatelycontains a mechanical filter media and/or a filter media such assilver-carbon, copper or zinc, all of which are known anti-bacterialmaterials.

Referring again to FIG. 2, in the preferred embodiment of the presentinvention the incoming stream of water 24 enters the machine 28 throughthe inlet 25 and goes into the reservoir 14, where it mixes with anywater already in the reservoir. Thus, the stream of water 15 carried bythe transport conduit 30 toward and beyond the treatment device 32,32a-d constitutes a mixture of water from the incoming stream 24 andrecirculating water already present in the reservoir 14. In starkcontrast to the conventional arrangement depicted in FIG. 1, both waterfrom the incoming stream and recirculating water are treated beforearriving at and flowing over the evaporator plate 12, which reduces thelikelihood of ice being formed from contaminated water.

The present invention contemplates many ways of arranging the flow ofwater into and through the ice-making machine 28. In FIG. 2, forexample, both fresh and recirculated water are mixed in the reservoir 14prior to being pumped by the recirculating pump 16 in the stream 15 pastthe treatment device 32.

Referring now to FIG. 8, an alternate embodiment is shown and generallydesignated 28a, in which an incoming stream of water 62 and a stream ofwater from the reservoir 64 are carried by or through the treatmentdevice 32, 32a-d in separate transport conduits, 66 and 68 respectively.The separate streams of water 62, 64 become mixed only at the waterdistributor 20, before passing over the evaporator plate 12 and into thereservoir 14. Other water transport arrangements are contemplated, solong as all streams of water encounter the treatment device, and aretreated, before flowing over the evaporator plate 12. This ensures thatall ice is made from treated water.

Thus, the present system for treating water in ice-making machines cangreatly reduce the chance of contaminated ice, and can greatly reducethe amount of scale build-up in the machine, by removing dirt from thewater. Similarly, ice made according to a method comprising the presentinvention, and any ice-making machine which incorporates the presentsystem, is a significant improvement over prior art methods andmachines, in terms of water treatment and contaminant-free ice.

While particular embodiments of the present invention's disinfectionsystem for ice-making machines has been shown and described, it will beappreciated by those skilled in the art that changes and modificationsmay be made thereto without departing from the invention in its broaderaspects and as set forth in the following claims.

What is claimed is:
 1. A system for treating water in an ice-makingmachine having a water inlet for receiving an incoming stream of water,a supply of recirculating water, a reservoir for containing said supply,a pump for pumping water from the reservoir, a transport conduit incommunication with the pump for transporting pumped water from thereservoir to an evaporator plate, and the evaporator plate receiveswater from the transport conduit and over which at least one of theincoming stream and the recirculating supply of water can flow to formice, water flowing from the evaporator plate is received in thereservoir for recirculation, said system comprising:means for treatingat least one of the incoming stream and the recirculating supply in thetransport conduit, said means for treating being disposed in operationalrelationship to the transport conduit between the pump and theevaporator plate so that all water passing through the conduit istreated just prior to at least one of the stream and the supply flowingover said evaporator plate.
 2. The system of claim 1 wherein saidtreatment means comprises at least one disinfection device including anozone generator disposed for introducing ozone into the water for ozonetreatment of the water.
 3. The system of claim 1 wherein said treatmentmeans comprises at least one filtration device.
 4. The system of claim 3wherein said at least one filtration device includes a filter mediaincorporating anti-bacterial materials selected from the groupconsisting of hollow fibers, a membrane, halogenated resin,silver-carbon, mechanical filters, copper and zinc.
 5. The system ofclaim 1 wherein said treatment means comprises at least one ultravioletdisinfection device.
 6. The system of claim 5 wherein said disinfectiondevice comprises:at least one ultraviolet lamp; and transport means fortransporting at least one of said incoming stream of water and saidrecirculating water past said ultraviolet lamp and exposing said waterto said lamp.
 7. The system of claim 6 wherein said transport meanscomprises at least one tube.
 8. The system of claim 7 wherein said atleast one tube includes a first tube which carries a first stream ofwater, and a second tube which carries a second stream of water, pastsaid at least one ultraviolet lamp.
 9. The system of claim 7 whereinsaid at least one tube is comprised of material that is transparent toultraviolet radiation.
 10. The system of claim 9 wherein said at leastone tube is wound into an approximately spiral shape.
 11. The system ofclaim 10 wherein said ultraviolet lamp is placed approximately into acenter of said spiral shape formed by said tube.
 12. A method for makingice with treated water, comprising the steps of:providing an incomingstream of water to an ice-making machine having a water inlet forreceiving an incoming stream of water, a supply of recirculating water,a reservoir for containing said supply, a pump for pumping water fromthe reservoir a transport conduit for transporting pumped water from thereservoir to an evaporator plate, the evaporator plate receives waterfrom the transport conduit and over which at least one of said incomingstream and said recirculating supply of water can flow to form ice,water flowing from the evaporator plate is received in the reservoir forrecirculation; exposing at least one of the incoming stream of water andthe recirculating supply to a disinfectant treatment means beingdisposed in operational relationship to the transport conduit betweenthe pump and the evaporator plate so that all water passing through theconduit is treated just prior to at least one of the stream and thesupply flowing over said evaporator plate; and chilling and freezing aportion of at least one of said incoming stream and said recirculatingsupply to make a supply of ice on said evaporator plate.
 13. The methodof claim 12 wherein said treatment means comprises at least oneultraviolet disinfection device.
 14. The method of claim 13 wherein saidat least one ultraviolet disinfection device comprises:at least oneultraviolet lamp; and transport means for transporting at least one ofsaid incoming stream and said recirculating supply past said ultravioletlamp.
 15. The method of claim 14 wherein said transport means comprisesat least one tube.
 16. The method of claim 15 wherein said at least onetube includes a first tube which carries a first stream of water, and asecond tube which carries a second stream of water past said at leastone ultraviolet lamp.
 17. The method of claim 15 wherein said at leastone tube is comprised of material that is transparent to ultravioletradiation.
 18. The method of claim 17 wherein said at least one tube iswound into an approximately spiral shape.
 19. The method of claim 18wherein said ultraviolet lamp is placed approximately into a center ofsaid spiral shape formed by said tube.
 20. The method of claim 12wherein said treatment means comprises at least one disinfection deviceincluding an ozone generator disposed for introducing ozone into thewater for ozone treatment of the water.
 21. The method of claim 12wherein said treatment means comprises at least one filtration device.22. The method of claim 21 wherein said at least one filtration deviceincorporating anti-bacterial materials selected from the groupconsisting of hollow fibers, membrane material, halogenated resin,silver-carbon, copper and zinc.
 23. An ice-making machine comprising:awater inlet for receiving an incoming stream of water; a supply ofrecirculating water; a reservoir for containing the supply; a pump forpumping the supply from the reservoir; a transport conduit fortransporting water pumped from the reservoir; an evaporator plate influid communication with the transport conduit, which receives waterfrom the transport conduit and over which at least one of said incomingstream and said recirculating supply can flow to form ice; saidreservoir disposed relative to said evaporator plate to receive waterflowing from said evaporator plate for recirculation; and means fortreating at least one of the incoming stream and the recirculatingsupply in the transport conduit, said means for treating havingdisinfectant properties and being disposed in operational relationshipto the transport conduit between the pump and the evaporator plate sothat all water passing through the conduit is treated just prior to atleast one of the stream and the supply flowing over said evaporatorplate.
 24. The ice-making machine of claim 23 wherein said treatmentmeans comprises at least one ultraviolet disinfection device.
 25. Theice-making machine of claim 24 wherein said ultraviolet disinfectiondevice comprises:at least one ultraviolet lamp; and transport means fortransporting at least one of said incoming stream and said recirculatingsupply past said ultraviolet lamp, wherein said transport meanscomprises at least one tube comprised of material that is transparent toultraviolet radiation and which is wound into a spiral shape.
 26. Theice-making machine of claim 25 wherein said at least one tube includes afirst tube which carries a first stream of water, and a second tubewhich carries a second stream of water, past said at least oneultraviolet lamp.
 27. The ice-making machine of claim 25 wherein saidultraviolet lamp is placed into the center of said spiral shape formedby said at least one tube.
 28. The ice-making machine of claim 23wherein said treatment means comprises at least one filtration device.29. The ice-making machine of claim 28 wherein said at least onefiltration device incorporates anti-bacterial materials selected fromthe group consisting of hollow fibers, membrane material, halogenatedresin, silver-carbon, copper and zinc.